Various ideas have been incorporated into turbine power generation equipment (turbine equipment) having a compressor, a combustor and a turbine in order to increase an electrical efficiency and a thermal efficiency. Of them, an idea of bleeding air from the compressor, and introducing it into the turbine to cool turbine blades has been put into practice. Cooling of the stationary blades of the turbine is performed by bleeding compressed air having a pressure corresponding to a stationary blade stage from the compressor, and introducing it into the site of a predetermined stage of the turbine. Cooling of rotor blades of the turbine is performed by introducing part of discharge air from the compressor into the turbine.
Conventional turbine equipment consumed a large amount of compressed air, because much air is required for cooling of the blades. Blade cooling air has a very low rate of conversion into output by turbine stages, and has decreased the rate of conversion into turbine output.
The present invention has been accomplished in view of the above circumstances, and its object is to provide turbine equipment capable of sufficiently cooling turbine blades while saving compressed air.